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In this paper, prehydrolysis was used as the first treatment of poplar slab for producing high-grade dissolving pulp, the optimum prehydrolysis conditions of poplar were obtained as followings: liquid ratio 1:6, H2SO41.0%, the highest temperature of 160±5°C, heating time of 90min, holding time of 120min. Hydrolyzed poplar slab was cooked to determine the effects of various alkali charges on pentosans, alpha-cellulose, kappa number, and degree ofpolymerization (DP). The optimum cooking process conditions of poplar were obtained as followings: alkali dosage 24%, sulfidity 5% ,the highest temperature of 160±5°C, heating time of 60min, holding time of 120min.Cooked pulps were bleached using Op-Q-P sequence. As a consequence, the poplar slab dissolving pulp of pentosan 3.73%, alpha-cellulose 95.13%,kappa number1.58, brightness 86.4%ISO, degree of polymerization (DP) 488.84 was obtained in our laboratory.

Aluminium silicate fiber is an excellent high-temperature material which is widely used in special paper industry in recent years. Due to its property of hardly interweave into the paper and the low strength of the single inorganic fibers paper, it is difficult to make a general basis weight paper. In response to these issues, the strength of the paper was improved by adding some plant fibers. This study takes advantage of good resistance to high temperature of inorganic adhesive and bonding capacity of organic intensifier. Meanwhile two inorganic adhesives (waterglass and ludox) and one organic adhesives carboxymethy starch (CMS) were used in the process of preparing the aluminium silicate paper. The physical properties and insulation properties of the paper which prepared from the difference conditions were studied. The experiment results showed that the adhesive of waterglass and ludox can improve the properties of resistant to high temperature. The adding dosages were 10% and 7.5ml, respectively. The best ratio of alumina silicate fiber to conifier fiber is 7 to 3.The using of CMS can decrease the amount of the plant fiber and its best usage is 10%.

The stickies in pulp and paper machinery especially in the blankets will cause a lot of problems such as paper defects, increasing the time of machine shut down . Therefore, Inhibiting the Stickies of blanket is very important to regular production. In this study,we mainly studied on the inhibition of Stickies in the blanket with enzyme. The processed blanket was treated by several kinds of enzymes. The results showed that the optimum enzyme treatment conditions were obtained as followings:PH of 7, temperature of 50°C, 2×104U/g of cellulose enzyme, 2×103U/g of amylase and 104U/g of lipase. The blankets obtained better cleaning situation under this conditions.

The tensile test of casting ferritic stainless steel was conducted on SHIMADZU AG-10 at different temperatures of 300, 500, 600, 700, 800, and 950°C, respectively. The engineering stress-strain curves with the thermal deformation at the different temperatures, the tensile strength and elongation curves were obtained. Metallographic test samples were prepared and the morphology of deforming zone was observed by optical microscopy. The experimental results showed that the tensile strength of the test samples decreased with increasing temperature. From 300 to 500°C, the work hardening occurred and the tensile strength increased with increasing engineering strain. The softening occurred and the tensile strength decreased with increasing engineering strain at temperatures from 600 to 950°C. The strength of 430 stainless steel decreased, and the plasticity increased with the increase in temperature. The fractures were basically intergranular fractures within the range of 300~950°C. A transition occurred to the form of fracture from the ductile to the brittle, which might be related to the nitrogen atom in the 430. Grain deformation along specimen tensile direction concentrated in the necking region, where appeared banded structure in martensite. The organization at the edge of the sample was fine, while the organization at the central region was coarser.

Olympic torches are the fantastic combination of successful design, appropriate materials and optimum processing which are the basic concept concepts in the major of Materials science and engineering. London Olympic torch was designed to be a three-sided pyramidal in shape, reflecting the features of the Olympic host country and the implication of designers. The material of Olympic torch selected aluminum alloys with a lightweight, high-strength, low thermal conductivity and environmentally friendly recycle; if low weight and high strength are key criteria for the torch, perhaps we can look forward to the incorporation of grapheme in the 2016 Olympic Games torch. The processing of Olympic torch involved laser cutting for 8000 holes and physical vapor deposition for gold-colored titanium nitride film on the surface of the aluminum plates, which embodied the best manufacturing route and the host country's technological capabilities.

According to the arrangement of atoms, the solid materials can be divided into the crystals and the non-crystals. Short for quasi-periodicity crystal, quasicrystal, also known as the "quasi crystal" or "mimetic crystal", is an intermediate between crystals and non-crystals. Three mathematical laws hidden in the quasicrystal are Penrose puzzles, Fibonacci sequence and golden section, and the uniqueness of quasicrystals is five rotational symmetry nonexistent in common crystals. A few quasicrystals (such as Al65Cu20Fe10Mn5, Al75Fe10Pd15) are stable phases, while most of the quasicrystals belong to the metastable products, both of which are formed largely by the method of rapid cooling. Quasicrystal materials have a very high hardness, low coefficient of friction and non-stick characteristic, of which the unique performance is successfully applied in the frying pans, razor blades and surgical tools.

The mechanical and physical properties of metals are closely related to engineering applications. As ecological materials, color, taste and toxicity of metals should be taken into consideration. Metals have specific colors, such as gold, silver, bronze and iron. "Metallic taste" is another taste different from the sour, sweet, bitter, saltiness and umami. Directives in European Union reveal different toxicities on the health hazards.

In this paper, we studied the possibility of wood powder in place of mechanical pulp in paper making to get high bulkness, also the dry-bleaching method of wood powder, the strength enhancement and retention effect for wood powder during paper making were all introduced and analyzed in detail.

The residues from wheat straw pulping mainly include uncooked chips and fiber bundles. In order to achieve high quality pulp, the residues require removal from the system. It was not necessary that the residues were re-cooked because of its high contents of non-cellulosic constituent. The achievement of low density foamed buffer material with the residues of wheat straw pulping would make the second pollution problem of the residues be solved, and achieve a replacer of foamed plastic material. The paper discussed the producing techniques of foamed buffer material with the residues of wheat straw pulping. The result showed that the best foamed properties of the residues were achieved with proper dosage of natural bonding agent like wheat flour, inorganic foamed agent, crosslink agent, and proper foamed temperature. The density and compression of foamed buffer material with the residues of wheat straw pulping were achieved with 60 kg /m3 and 60 kPa respectively at the optimum foaming condition.

The paper studied the possibility of using the whole stalk kenaf as a raw material for producing high yield and good quality bleachable pulp. The stem of kenaf has two distinct parts: the bast and the core. which have markedly different chemical components and fiber morphology. In general, the length of bast fiber ranges from about 2-2.5mm, while that of the core varies from about 0.5-0.8mm, so it is important to achieve a balance of the bast fiber and the core during pulping. The study indicated that using the selected continuous cooking conditions, the properties of kenaf pulp approached to the hardwood pulp and would be easily bleached.